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Linking Predation Risk, Herbivore Physiological Stress and Microbial Decomposition of Plant Litter
Published on: March 12, 2013
Dynamics of a subterranean trophic cascade in space and time
Karthik Ram1, Daniel S Gruner, John P McLaughlin
1Section of Evolution and Ecology, University of California, Davis, CA. Bodega Marine Lab, UC Davis, Bodega Bay, CA. Department of Entomology, University of Maryland, College Park, MD. Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, CA. Department of Biology, University of Rhode Island, Kingston, RI.
Journal of Nematology
|March 5, 2009
Summary
Entomopathogenic nematodes (EPNs) show promise for biological control but often fail to persist in the field. This study investigated the persistence of Heterorhabditis marelatus in California coastal prairies, identifying key ecological factors.
Area of Science:
- Ecology
- Biological Control
- Nematology
Background:
- Trophic cascades underpin biological control of insect pests.
- Entomopathogenic nematodes (EPNs) are lethal to insect pests but often fail to establish in field conditions.
- Persistence of EPNs is influenced by abiotic factors, host availability, and movement.
Purpose of the Study:
- To review 13 years of research on the endemic population of Heterorhabditis marelatus in a California coastal prairie.
- To understand the ecological factors influencing the persistence of H. marelatus.
- To provide insights for improving biological control programs using EPNs.
Main Methods:
- Long-term field studies on EPN biology and ecology.
- Laboratory experiments to investigate persistence mechanisms.
- Analysis of abiotic conditions, soil variation, vegetation structure, and host availability.
Main Results:
- Natural populations of H. marelatus persisted at varying incidences across different sites within the study area.
- The seasonal abiotic environment and variations in soil, vegetation, and host availability influenced EPN persistence.
- Mechanisms and hypotheses for H. marelatus persistence were identified through field and lab experiments.
Conclusions:
- Ecological studies of natural EPN populations are crucial for understanding persistence.
- Insights gained can significantly improve the practice and management of EPN-based biological control.
- Further research on naturally occurring EPNs can enhance control of soil-dwelling insect pests.
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